Mosquitoes have an extraordinary ability to target humans far away and fly straight to their unprotected skin. Regrettably, mosquitoes can do more than cause an itchy(发痒的)wound. Some mosquitoes spread several serious diseases, including Dengue, yellow fever and malaria.

Over one million people worldwide die from these diseases each year. New research now shows how mosquitoes choose who to bite.

Mosquitoes need blood to survive. They are attracted to human skin and breath. They smell the carbon dioxide gas, which all mammals breathe out. This gas is the main way for mosquitoes to know that a warm-blooded creature is nearby.

But mosquitoes also use their eyes and sense of touch. Michael Dickinson is a professor at the California Institute of Technology. His research shows how these small insects, with even smaller brains, use three senses to find a blood meal.

Michael Dickinson’s team used plumes—a material that rises into the air of carbon dioxide gas into a wind tunnel. They then used cameras to record the mosquitoes. The insects followed the plume.

Then, the scientists placed dark objects on the lighter colored floor and walls of the tunnel. Mr Dickinson said, at first, the mosquitoes showed no interest in the objects at all.

“What was quite striking and quite surprising is that the mosquitoes fly back and forth for hours. These are hungry females and they completely ignore the objects on the floor and wall of the tunnel. But the moment they get a hit of CO2, they change their behavior quite obviously and now would become attracted to these little visual blobs (斑点).”

This suggested to the researchers that a mosquito’s sense of smell is more important in the search for food. Once mosquitoes catch a smell of a human or animal, they also follow visual signals.

1.What do mosquitoes mainly use to find their targets?

A. Sense of smell. B. Sense of touch.

C. Sense of sight. D. Smart brains.

2.The first response of the mosquitoes to the objects in the experiment is .

A. to fly to the dark ones

B. to catch and stick to them

C. to take no notice of them

D. to attach themselves to them

3.How can we avoid being attacked by mosquitoes according to the text ?

A. Don’t let them see us.

B. Use dark objects to stop them.

C. Make them fly back and forth for hours.

D. Attract them to objects full of carbon dioxide gas.

4.What can be the best title for the text?

A. How Do Mosquitoes Survive?

B. Why Do Mosquitoes Need Blood?

C. How Do Mosquitoes Choose to Bite You?

D. Why Do Mosquitoes Attack the Human Being?

完形填空阅读下面短文,掌握其大意,从短文后各题所给的四个选项(A、B、、C、D)中,选出可以填入空白处的最佳选项。

After a long day at school,I walked home with my heavy schoolbag.Sleepy and________,I threw my things on the couch and grabbed something from the________to eat.I passed by the living room and wished I could watch TV,but I knew my ________ would take me the whole night.I took my schoolbag and went ________to my room.I tried to understand chemistry and ________sleepiness at the same time.I tried to keep my eyes ________and I wanted something to cheer me up.

Later, I________the sound of the front door opening.And I waited for it—the sound of my mom singing. Though she sang off-key(跑调),________ made me excited that she was here.I ran down to________my mom.We hugged each other and talked for a while.I like it when my mom was happy.Her________seemed to flow down to me and I got the strength to________the stress again.

Sometimes, I wonder how my mom can still be ________after coming back from work.Every weekday,she wakes up________in the morning to go to work and spends all hour on the bus before getting downtown.At a ________factory,she works standing for the whole day and draws patterns for clothes over and over.After work,my mom at times gets stuck in________ for two hours on her way back home.When I________my school life with her work life, I should not be the one to________.At least I have some interesting things to do at school, but one mistake at work can cost my mom her job.I ________that my mom has a positive attitude and lives her life with a joyous heart,which encourages me to do my work well, ________there may be difficulties.Seeing her happy makes me feel________,too.

1.A. heavy B. busy C. hungry D. unlucky

2.A. classroom B. kitchen C. bedroom D. apartment

3.A. dream B. supper C. homework D. experience

4.A. downstairs B. outside C. upstairs D. inside

5.A. break off B. put off C. get off D. fight off

6.A. opening B. opened C. open D. closing

7.A. felt B. listened C. raised D. heard

8.A. which B. that C. it D. but

9.A. Look B. greet C. said to D. help

10.A. need B. idea C. faith D. energy

11.A. face B. change C. accept D. 1eave

12.A. creative B. sensitive C. competitive D. positive

13.A. early B. soon C. fast D. 1ate

14.A. furniture B. shoe C. car D. clothing

15.A. chat B. traffic C. duty D. task

16.A. replace B. exchange C. connect D. compare

17.A. complain B. decide C. study D. play

18.A. achieve B. notice C. appreciate D. improve

19.A. however B. though C. despite D. at least

20.A. good B. skillful C. successful D. important

When we’re little, our mother is the center of our attention, and we are the center of hers.

So our mother’ characteristics leave an indelible(持久的)impression, and we are forever after attracted to people with her facial features, body type, personality, even sense of humor. If our mother is warm and giving, as adults we tend to be attracted to people who are warm and giving. If our mother is strong and even-tempered, we are going to be attracted to a fair-minded strength in our mates(伴侣).

The mother has an additional influence on her sons: she not only gives them clues to what they will find attractive in a mate, but also affects how they feel about women in general. So if she is warm and nice, her sons are going to think that’s the way women are. They will probably grow up to be warm and responsive lovers and also be cooperative around the house.

Conversely(相反的), a mother who has a depressive personality, and is sometimes friendly but then suddenly turns cold and rejecting, may raise a man who becomes a “dance-away lover”. Because he’s been so scared about love from his mother, he’s afraid of commitment and may pull away from a girlfriend for this reason.

While the mother determines in large part what qualities attract us in a mate, it’s the father—the first male in our lives—who influences how we relate to the opposite sex. Fathers have an enormous effect on their children’s personalities and chances of marital(婚姻的) happiness.

Just as mothers influence their son’s general feelings toward women, fathers influence their daughter’s general feelings about men. If a father lavishes praise on his daughter and demonstrates that she is a worthwhile person, she’ll feel very good about herself in relation to men. But if the father is cold, critical or absent, the daughter will tend to feel she’s not very lovable or attractive.

In addition, most of us grow up with people of similar social circumstances. We hang around with people in the same town; our friends have about the same educational backgrounds and career goals. We tend to be most comfortable with these people, and therefore we tend to link up with others whose families are often much like our own.

1.Why do our mother’s characteristics leave us an indelible impression?

A. Because we are likely to be attached to people with her characteristics.

B. Because mother and her child are the centers of each other when her child is very young.

C. Because our mother is better than our dad.

D. Because our mother is a woman who is kind to us.

2.What can we know from Paragraphs 2 and 3?

A. The mother only influences her sons.

B. The sons always think women are warm and nice.

C. A mother who has a depressive personality is sure to raise a dance-away lover.

D. The mother has an additional influence on her sons.

3.Which of the following is NOT true?

A. If our mother is warm and giving, we love to be together with warm and generous people.

B. If our mother is strong and even-tempered, we are going to be attracted to a fair-minded strength in our mates.

C. Mother not only gives her children clues to what they will find attractive in a mate, but also affects how they feel about women in general.

D. Fathers influence their daughter’s general feelings about men.

4.What does the underlined word “lavishes” in Paragraph 5 probably mean?

A. Uses much. B. Uses little.

C. Never uses. D. Seldom uses.

5.What does the passage mainly talk about?

A. Mothers’ influence on their sons.

B. Parents’ influence on their children.

C. Parents’ impression on their children.

D. Fathers’ influence on their daughters.

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

Question: I have been learning English for about 7 years. 1.________ And I still can’t make myself understood in English. However, I love learning English. How can I learn English well? Please help me.

Answer: Many people have asked me this question. 2.________ Here I will give you several tips for learning English.

●3.________

First of all, you must want to learn. If you are not interested in learning English, no class will help you and no book will help you. So you have to be honest with yourself. Ask yourself, “Do I really want to learn English?” If you can’t answer “yes” to this question, it is better for you to set English aside until you’re ready and willing to learn.

● Set goals (目标).

To learn English well, you must set some goals. 4.________ It will also help you to see your progress. Ask yourself, “What are my goals? What areas would I like to improve?” Think about what your goals are, and review once in a while to see that you are making progress toward your goals.

● Practice, practice, and practice.

After you have set your goals, you have a better idea of what you need to practice. Just like the athlete whose goal is the Olympics must train daily, you as a language learner must practice language every day to make progress toward your goal. 5.________

A. Want to learn.

B. I think it is not easy to learn it well.

C. Make friends with some Americans online.

D. Reading is a very good way to learn new words.

E. The answers are as different as the people asking the question.

F. The more you practice, the more progress you will make.

G. Having goals will help you remember what areas you want to work on.

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